The Electrical and Magnetic Properties of Amorphous Pd-Cu-P Alloys

The Electrical and Magnetic Properties of Amorphous Pd-Cu-P Alloys
Author: Gregory Ligot Tangonan
Publisher:
Total Pages: 186
Release: 1976
Genre: Amorphous substances
ISBN:

The amorphous phases of the Pd-Cu-P system has been obtained using the technique of rapidly quenching from the liquid state. Broad maxima in the diffraction pattern were obtained in the X-ray diffraction studies which are indicative of a glass-like structure. The composition range over which the amorphous solid phase is retained for the Pd-Cu-P system is (Pd100[subscript x]Cu[subscript x])0P20 with 10 d"x d"50 and (Pd65Cu35)100−[subscript y]P[subscript y] with 15 d"y d"24 and (Pd60Cu40)100−[subscript y]P[subscript y] with 15 d"y d"24. The electrical resistivity for the Pd-Cu-P alloys decreases with temperature as T2 at low temperatures and as T at high temperatures up to the crystallization temperature. The structural scattering model of the resistivity proposed by Sinha and the spin-fluctuation resistivity model proposed by Hasegawa are re-examined in the light of the similarity of this result to the Pt-Ni-P and Pd-Ni-P systems. Objections are raised to these interpretations of the resistivity results and an alternate model is proposed consistent with the new results on Pd-Cu-P and the observation of similar effects in crystalline transition metal alloys. The observed negative temperature coefficients of resistivity in these amorphous alloys are thus interpreted as being due to the modification of the density of states with temperature through the electron-phonon interaction. The weak Pauli paramagnetism of the Pd-Cu-P, Pt-Ni-P and Pd-Ni-P alloys is interpreted as being modifications of the transition d-states as a result of the formation of strong transition metal-metalloid bonds rather than a large transfer of electrons from the glass former atoms (P in this case) to the d-band of the transition metal in a rigid band picture.

Amorphous Magnetism and Metallic Magnetic Materials - Digest

Amorphous Magnetism and Metallic Magnetic Materials - Digest
Author: A.R. Ferchmin
Publisher: Elsevier
Total Pages: 367
Release: 1983-09-01
Genre: Technology & Engineering
ISBN: 1483290603

This unique book provides the reader with the only comprehensive overview of the subject. It is an indispensable reference source in that it attempts to compress into one single volume the whole body of basic and applied research on amorphous magnetic metallic materials.Supplements to the Journal of Magnetism and Magnetic Materials appear regularly keeping the information contained in this book as up-to-date as possible. The book has been designed for easy use and is a must for researchers in the field.

Conduction-electron Localized-moment Interaction in Palladium-silicon Base Amorphous Alloys Containing Transition Metals

Conduction-electron Localized-moment Interaction in Palladium-silicon Base Amorphous Alloys Containing Transition Metals
Author: Ryusuke Hasegawa
Publisher:
Total Pages: 202
Release: 1969
Genre: Amorphous substances
ISBN:

The electrical and magnetic properties of amorphous alloys obtained by rapid quenching from the liquid state have been studied. The composition of these alloys corresponds to the general formula MxPd80-xSi20, in which M stands for a metal of the first transition series between chromium and nickel and x is its atomic concentration. The concentration ranges within which an amorphous structure could be obtained were: from 0 to 7 for Cr, Mn and Fe, from 0 to 11 for Co and from 0 to 15 for Ni. A well-defined minimum in the resistivity vs temperature curve was observed for all alloys except those containing nickel. The alloys for which a resistivity minimum was observed had a negative magnetoresistivity approximately proportional to the square of the magnetization and their susceptibility obeyed the Curie-Weiss law in a wide temperature range. For concentrated Fe and Co alloys the resistivity minimum was found to coexist with ferromagnetism. These observations lead to the conclusion that the present results are due to a s-d exchange interaction. The unusually high resistivity minimum temperature observed in the Cr alloys is interpreted as a result of a high Kondo temperature and a large s-d exchange integral. A low Fermi energy of the amorphous alloys (3.5 eV) is also responsible for the anomalies due to the s-d exchange interaction.

Magnetic and Electrical Properties of Amorphous Pd--Co--P Alloys

Magnetic and Electrical Properties of Amorphous Pd--Co--P Alloys
Author:
Publisher:
Total Pages:
Release: 1973
Genre:
ISBN:

The magnetic properties of Pd- Co- P alloys show that they are ferromagnetic with a Curie temperature between 272 and 399 deg K as the cobalt concentration increases from 15 to 50 at.%. Below 20 at.% Co the short-range exchange interactions which produce the ferromagnetism are unable to establish a long-range magnetic order and a peak in the magnetization shows up at the lowest temperature range undei an applied field of 6.0 KOe. The electric resistivity measurements were performed from liquid helium temperature up to the vicinity of the melting point (900 deg K). The electrical resistivity of Pd-Co- P shows the coexistence of a Kondo-like minimum with ferromagnetism. The minimum becomes less important as the transition metal concentration increases and the coefficients of In T and T/sup 2/ become smaller and strongly temperature dependent. The spin ordering in these kinds of alloys can be simulated as the ordering due to an applied external field or as an increase in internal fields, due to an increase in transition metal concentration. The negative magnetoresistivity is a strong indication of the existence of localized moment. (auth).

Glassy Metals: Magnetic, Chemical and Structural Properties

Glassy Metals: Magnetic, Chemical and Structural Properties
Author: Ryusuke Hasegawa
Publisher: CRC Press
Total Pages: 288
Release: 2018-01-18
Genre: Science
ISBN: 1351080717

Covers: structure of metallic glass alloys; theory of magnetism in noncrystalline solids; electronic structure of metallic glasses; magnetism in transition metal base amorphous alloys; application of metallic glasses in low-frequency magnetic devices; magnetic material properties and applications of metallic glasses in electronic devices; rare-earth transition metal base alloys; corrosion properties of amorphous alloys.

Metastable Alloys: Preparation and Properties

Metastable Alloys: Preparation and Properties
Author: K.W. Samwer
Publisher: Elsevier
Total Pages: 677
Release: 2014-01-13
Genre: Technology & Engineering
ISBN: 008098360X

This volume contains most of the papers presented at symposium D, one of the four symposia that formed the 1988 Strasbourg Spring Conference. The three day programme consisted of nine oral sessions; a poster session and a plenary talk giving an overview of current topics in hard magnetic materials. Scientists involved in basic as well as applied research concentrated their discussions on the fundamental processes relevant for the formation of metastable alloys such as amorphous alloys (metallic glasses), microcrystalline, quasicrystalline and nanocrystalline alloys and their applications. These materials are proving to be of considerable interest to research workers because of their possible application in the electronics industry, e.g. as diffusion barriers in devices or as data storage media.